Body's Response to Infection

Question 1

Lymphocytes

Answer 1

WBCs that cause adaptive immunity

Question 2

Primary lymphoid organs

Answer 2

Organs where lymphocytes develop from stem cell precursors

Bone Marrow
Thymus

Question 3

Thymus

Answer 3

Site of T lymphocyte development after their precursor is formed

It is a primary lymphoid organ

Question 4

Secondary Lymphoid Tissues and 3 Examples

Answer 4

Where mature lymphocyte cells accumulate

Lymph Nodes
Spleen
Mucosal Tissues

Question 5

Peripheral Tissue

Answer 5

Non lymphatic tissues of the body where lymphocytes can pass into, which then leave in tissue fluid through afferent lymphatics

Question 6

What happens after lymphocytes spend a couple days in lymph nodes

Answer 6

They go to the thoracic duct through the efferent lymphatic where they recirculate around the body to search for pathogens
(this is not 100% accurate)

Question 7

Two Types of T Cells

Answer 7

CD8+ Tc (Cytotoxic) Lymphocytes
[Killing other cells of the body - infected]

CD4+ Th (Helper) Lymphocytes
[Helping to activate other immune cells]

Question 8

Which cells are granulocytes/polymorphonuclear (have nuclei with arm like thingies)

Answer 8

Neutrophils
Eosinophils
Basophils

Mast Cells

Question 9

Mononuclear Cells

Answer 9

Cells with simple nuclear shapes

Monocytes/Macrophages
Dendritic Cells
Natural Killer Cells
Lymphocytes

Question 10

Monocytes

Answer 10

Circulating cells that can migrate into tissues and differentiate into macrophages

Question 11

Dendritic Cells

Answer 11

Carry out arm like or dendritic processes

Question 12

Natural Killer Cells

Answer 12

Responsible for killing early tumour cells as well as infected cells

Question 13

Neutrophils

Answer 13

Type of phagocyte that rush to the site of infection and digest the pathogen - most common type of WBC

Question 14

Lymphoid vs Myeloid Cells

Answer 14

(RBCs also myeloid)

Think of the progenitors in haematopoeisis

Question 15

3 Secreted mediators of immunity that are not proteins

Answer 15

Prostaglandins, Leukotriens and Histamines

Question 16

Two Main Conceptual Parts of Immunity

Answer 16

Recognition and Defence

Question 17

Which cells are innate and which are part of adaptive immunity

Answer 17

Question 18

Innate Immunity

Answer 18

In-born Immunity
Unspecialised
The same at each exposure to the same microbe
Good with weaker infections; not as good with stronger

Question 19

How do innate immune cells recognise pathogens as not foreign

Answer 19

Ability to detect Pathogen-Associated Molecular Patterns (PAMPs); e.g. Bacterial lipopolysaccharide or viral double stranded RNA

PAMPs bind to molecules on the surface (sometimes cytoplasm) of innate cells called Pattern Recognition Receptors (PRRs); e.g. toll-like receptors

Question 20

Adaptive/Acquired Immunity

Answer 20

Slowly Activated
Developed along with age
Improves on repeated exposure to same microbe
Can be highly efficient against even virulent pathogens
Specific response

Question 21

How do lymphocytes detect pathogens

Answer 21

Antigens detected by antigen specific receptors expressed on lymphocytes

Question 22

Stages of primary immune response - example of skin infection

Answer 22

• Epithelial Barrier cut
• Bacteria enter dermis and begin to replicate
• Come into contact with innate immune system and complement proteins; damage to bacteria but also produces inflammatory mediators
  
  • Inflamatory Mediators produced by mast cells which activate walls of nearby blood vessels making them leaky to allow leukocytes and fluid with complement proteins to leave blood stream and enter infected tissue
• Simultaneously, adaptive immune response is being kicked off; antigens are carried from infected site to draining lymph node through afferent lymphatics either freely or by dendrites (Takes a few days)
• Specialised AND activated lymphocytes can leave lymph nodes and go to site of infection through bloodstream
• Some lymphocytes don’t involve themselves with treating infection, instead become memory T and B cells associated with memory of those same antigens which can be reactivated much more quickly and intensely to manage future infection

Question 23

Different categories of infections and what immune components deal with them

Answer 23

Question 24

How does intra-cellular vesicular infection occur

Answer 24

Phagocytosed pathogens that are too resistant to being digested - e.g. TB Bacteria

Question 25

Interferon Proteins

Answer 25

Proteins that block virus’ abilities to replicate in cells

Question 26

Immunopathology

Answer 26

Diseases involving defects in, or inappropriate activity of the immune system

Question 27

Primary vs Secondary Immunodeficiency

Answer 27

Primary - Mainly genetics where mutations caused inhereted deficiency
Secondary - Acquired defects in immunity

Question 28

SCID (Severe combined immunodeficiency) and treatment

Answer 28

Primary Immunodeficiency

Lacking ability to make either form of lymphocyte

Bone Marrow Transplant

Question 29

Secondary Immunodeficiency example and describe it

Answer 29

HIV; targets protein on T Helper Cell surface (CD-4) and infects those cells, worsening the body’s ability to deal with infection

Question 30

Allergy

Answer 30

Hypersensitivity of immune response towards safe environmental molecules

Question 31

Sciencey word for Hayfever

Answer 31

Allergic Rhinitis

Question 32

Is transplant rejection an immunopathology

Answer 32

Yes

Question 33

Lymphoproliferative Diseases and examples

Answer 33

Immunopathology characterised by over production of lymphocytes

Lymphoma
Leukaemia
Myeloma